Morales-Arrieta Sandra, Rodríguez Maria Elena, Segovia Lorenzo, López-Munguía Agustín, Olvera-Carranza Clarita
Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, UNAM, Avenida Universidad 2001, Col. Chamilpa, Cuernavaca, Morelos 62250, México.
Gene. 2006 Jul 5;376(1):59-67. doi: 10.1016/j.gene.2006.02.007. Epub 2006 Apr 24.
A Leuconostoc mesenteroides NRRL B-512 F levansucrase gene, (levS), was isolated, sequenced and cloned in Escherichia coli. The recombinant enzyme was shown to be a fructosyltransferase producing a polymer identified by (13)C-NMR as levan. Based on sequence analysis, we found that this levansucrase is a mosaic protein, bearing structural features of glucosyltransferases in the amino and carboxy terminal regions similarly to inulosucrase from Leuconostoc citreum. The phylogenetic analysis of the C-terminal region domain of levansucrases from L. mesenteroides demonstrates that they group together into a novel putative sub-family of genes and evolved long before all other glucosyltransferases, while their catalytic domain structure is species related.
分离出肠系膜明串珠菌NRRL B - 512 F的果聚糖蔗糖酶基因（levS），对其进行测序并克隆到大肠杆菌中。重组酶显示为一种果糖基转移酶，可产生一种通过（13）C - NMR鉴定为果聚糖的聚合物。基于序列分析，我们发现这种果聚糖蔗糖酶是一种嵌合蛋白，在氨基和羧基末端区域具有葡糖基转移酶的结构特征，类似于柠檬明串珠菌的菊粉蔗糖酶。对肠系膜明串珠菌果聚糖蔗糖酶C末端区域结构域的系统发育分析表明，它们聚集在一起形成一个新的假定基因亚家族，并且在所有其他葡糖基转移酶之前很久就已进化，而它们的催化结构域结构与物种相关。
